Origins

Its name is a portmanteau of the phrase "no man's land" and "gnome".

Strategies

An easy way to obtain this achievement is to play the Story Quests to open new Areas in the Backyard. Each L.E.A.F. Agent room and each Top Zombie room has one hidden Golden Gnome and one Snow Globe in it. There are a total of 14 Golden Gnomes hidden around the Backyard. Once you collect around 5 gnomes, you will get a phone call from a payphone by the docks. If you answer it, a gnome will talk to you. After that, pick up the gnome bomb that has appeared by the docks and take it down to the sewers. This is used to blow up a wall. Once you go through the secret passage that the gnome bomb revealed, you can go down to the big structure and get this achievement.